I could never truly understand because my life never depended on learning the language, but I studied overseas for a semester in college. I was not good at speaking the language despite studying it for four years. I could understand it, read it, but not generate it myself. I got lucky to live with a family where two of the four spoke English.
But there were times when the English speakers were not there. It was just me trying to ask for help making breakfast or how to work my window. I would feel like a kindergartner with only a few words in my vocabulary. It was impossible not to feel stupid, and I was certain they thought I was. I spoke like I had a head injury.
It didn’t go any better in public. I stuck close to people who spoke English, and as a result, I never did become bilingual. I have the utmost respect for people who move to another country and learn a new language. I know, for a fact, I am not one of fluent ones. Props to your mother.